Triumph Stag Auto Reliability, MOT Pass Rate & Common Faults
Free Triumph Stag Auto car check
Is the Triumph Stag Auto reliable? We analysed 21,225 real MOT tests across 2,079 vehicles to find out.
Got a specific Triumph Stag Auto? Enter the reg for a free check:
The Triumph Stag Auto is above average for reliability based on real UK MOT data. Common problems include windscreen washer provides insufficient washer liquid, parking brake: efficiency below requirements and suspension component mounting prescribed area is excessively corroded. Here's everything you need to know before buying a used Triumph Stag Auto.
Triumph Stag Auto Number Plates
Number plates registered to a Triumph Stag Auto. Click on any registration for full vehicle details — including MOT history, mileage records, previous owners and damage history.
Triumph Stag Auto MOT Pass Rate by Year
How likely is a Triumph Stag Auto to pass its MOT? Here's the pass rate for each registration year, newest first.
Triumph Stag Auto Problems — What Goes Wrong?
The most common reasons a Triumph Stag Auto fails its MOT, ranked by how often they occur. Check for these problems before you buy.
Triumph Stag Auto Mileage — What's Normal?
How many miles does a typical Triumph Stag Auto owner drive per year? Use this to check if a car you're looking at has suspiciously low or high mileage.
Triumph Stag Auto MOT Data by Registration Year
Full breakdown of pass rate and mileage for each year. Use this to compare the Triumph Stag Auto year you're looking at.
| Year | Tests | Pass Rate | Low Mi. | Typical Mi. | High Mi. |
|---|---|---|---|---|---|
| 1978 | 1,952 | 76.2% | 37,168 | 56,939 | 75,693 |
| 1977 | 3,463 | 76.9% | 38,312 | 60,392 | 77,958 |
| 1976 | 4,363 | 75.5% | 31,047 | 62,979 | 80,065 |
| 1975 | 3,063 | 76.7% | 26,699 | 61,536 | 79,432 |
| 1974 | 2,975 | 77.7% | 26,156 | 63,295 | 83,507 |
| 1973 | 3,600 | 78.3% | 21,882 | 60,660 | 79,280 |
| 1972 | 1,496 | 77.7% | 16,482 | 51,762 | 77,852 |
| 1971 | 228 | 73.2% | 28,490 | 61,627 | 82,144 |
How Long Does a Triumph Stag Auto Last?
Based on 2,079 Triumph Stag Auto vehicles on UK roads.
Triumph Stag Auto Mileage Distribution
Total mileage recorded across all Triumph Stag Auto MOT tests. If the car you're looking at is above the 75th percentile, it's done more miles than most.
Best Year to Buy a Used Triumph Stag Auto
Based on MOT pass rates across all registration years with sufficient test data.
78.3% MOT pass rate from 3,600 tests
73.2% MOT pass rate from 228 tests
The best year to buy a used Triumph Stag Auto is 1973, which has the highest MOT pass rate at 78.3% across 3,600 tests. The 1971 model year has the lowest pass rate at 73.2% — if you're looking at one from that year, budget for potential repairs and get a thorough pre-purchase inspection.
How Does the Triumph Stag Auto Compare?
MOT pass rates compared to similar models. Click any model for the full breakdown.
| Model | Pass Rate | Tests | Typical Mileage | Lifespan |
|---|---|---|---|---|
| Triumph Stag Auto THIS CAR | 76.9% | 21,225 | 60,727 mi | 55 yrs |
| Triumph Bonneville | 90.1% | 235,206 | 7,823 mi | 53 yrs |
| Triumph Tiger | 90.6% | 196,853 | 17,026 mi | 32 yrs |
| Triumph Sprint | 87.3% | 158,613 | 21,242 mi | 33 yrs |
| Honda Civic Shuttle | 66.3% | 10,499 | 92,597 mi | 41 yrs |
Compared to the Triumph Bonneville (90.1% pass rate) and the Triumph Tiger (90.6% pass rate), the Triumph Stag Auto trails behind on MOT reliability.
Found a Triumph Stag Auto you like?
Run a full vehicle history check on the specific car. See finance, stolen, write-off, mileage and MOT data for that exact vehicle.
Check a specific Triumph Stag AutoShould you buy a used Triumph Stag Auto?
The Triumph Stag Auto has an overall MOT pass rate of 76.9% across 21,225 real MOT tests — comfortably above the UK average, which puts it among the more reliable models on UK roads.
The most common problems on the Triumph Stag Auto are windscreen washer provides insufficient washer liquid (740 recorded failures), parking brake: efficiency below requirements (550), and suspension component mounting prescribed area is excessively corroded (491). These are the faults most likely to cause an MOT failure on this model, so check for them carefully on any test drive or pre-purchase inspection. Many are wear-and-tear items that can be budgeted for, but a car that's already failing on multiple fronts may signal neglected maintenance.
A typical Triumph Stag Auto owner drives around 397 miles per year. If the car you're looking at is significantly above this, expect more wear on suspension, brakes and tyres. If it's well below, the vehicle may have been sitting unused — check for perished rubber, corroded discs and stale fluids.
In terms of longevity, most Triumph Stag Auto models stay on UK roads for around 55 years — a strong showing that suggests solid build quality and readily available parts. If you're buying one that's already approaching that window, the data suggests it has plenty of life left provided it's been maintained.
Before committing to a purchase, we recommend running a full vehicle history check on the specific car. This will reveal any outstanding finance, stolen markers, write-off history and mileage discrepancies that the seller may not disclose — and that the MOT data alone can't tell you.